Every OEM wheel that I have encountered has the width and offset stamped by the valve stem.

 

my wheels have the markings on the inside of the wheel

 

Yes, the small counter-sunk screws match up with holes in the stock hub and can be used to keep the spacer firmly in place. I use them although just to make sure they don't fall off when removing the wheel, but they aren't 100% necessary.

 

I would seek out hub centric front spacers. These will have a lip to set or center the wheel on when mounting...like the rear spacers will have. I tried the regular flat spacers in front and it was impossible to center the wheel and ended with a severe vibration. Sent the RSS spacers back.

 

Strange, I had no issue with the RSS front spacers but then I only did 5mm. I really appreciate the extra gap between the wheel and calipers when cleaning the red calipers now. And the tire sits nicely just inside the fender now.

 

Just the opposite. You want to add spacers when you drop the car since the drop tend to make the wheels look more tucked in.

 

What size spacer are your runnin on the back Rob ?

 

I will post pics but i just installed the GMP Spacers. 7mm and 15mm and it really makes a nice difference. Just enough to notice the wider look but not over powering. Really looks good. Thanks for the advice and support from the forum.

 

I just ordered the RSS 7mm spacers from SharkWerks as they ensured me they were hubcentric. What year is yours and which wheels are you running?

 

Don't like cross posting to other forums but here's a thread on sub-10mm hub centric spacers over at 6-speed

http://www.6speedonline.com/forums/9...c-spacers.html

 

An additional FYI related to this: One of our sponsors, Adaptec, came out with 7mm spacers that are both hub-centric (inward slot to accept the hub lip tightly) and wheel-centric (outward lip to align the wheel) about a year ago. I have these on my car and they work great. I think they posted a 20% off sale for black ones just a day or two ago, if black is your thing. Their galvanized bolts are holding up very well too.

 

+1 re: Adaptec. I dealt with the parent company/entity Motorsports Tech, and had them make a set of spacers for my C55 when fitting my OZ Superleggera IIIs purchased second hand. They can do just about anything. I wanted hub and wheel centric to eliminate any vibration issues, they easily accommodated. I think it was a 5mm spacer I ended up using.

On another note, I keep reading about 7mm/15mm spacers being the ideal/recommended set up for OE wheels, but I take it this applies to narrow body cars? My 06 C4S already has the 17mm spacers at the rear from the factory. Does this mean I should look at 32mm spacers for the rear, or just leave it as is and get spacers for the front?

 

Last question...notice some slight vibration at 60mph...can someone please tell me what would the proper torque be for 19inch wheels on the 997?

 

My research includes mixed findings. Originally 85 pound get was popular but the I read the factory upped that to 105.

Really, the torque should also be dependent on how hard your wheels are.

Regardless, I would be surprised if loose lug bolts were the cause of the vibration. I would verify balance and centering (do the latter first with the car in the air and a run out gauge).

 

These look,,, like really,,, ingenious :http://www.ogracing.com/brey-krause-...rs-porsche-911